Those hundreds of readers who, no doubt, regularly revisit past passages of BlackWatch wisdom will recall last May's comments on Tony Blair's long term retirement pledge.

"Premature, immature, and certain to split his party" was then our view. It has proved to be an understatement in spades. Harold Wilson handled it better in 1976. A sudden statement no-one anticipated. Limited replacement turmoil as a result.

We still await the final outcome this time round but certainly it has already produced one sharp shock. Tories have reached 40 per cent in the opinion polls for the first time since 1992. And this is, of course, the true basis for Labour's backbench disquiet. …

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